A bad tempered exchange between a supermarket worker and a shopper would not normally make the headlines, even in British "silly season" summertime.

But reports that an employee of Sainsbury’s – Britain's third largest supermarket chain – had refused to serve a shopper with a mobile phone clamped to her ear earlier this month caused a national whirl of excitement, with commentators and even Deputy Prime Minister Nick Clegg piling in.

When the incident, which took place in a London store, was first reported, on perhaps a quiet news day, Sainsbury’s issued a statement saying said it had apologized to the shopper and offered her some vouchers.

The company was subsequently besieged with messages of support for its employee. Commentators hailed her a heroine of righteousness. Mr. Clegg weighed in, telling a radio station that people talking on mobile phones during meetings “drives me round the bend. I have an old-fashioned view that people are supposed to talk to each other.”

Sainsbury's put out a later statement saying it was “pleased the story is leading to a wider debate on politeness."

The story was not about politeness, though. The supermarket worker had in fact forgotten her own manners by reprimanding a customer as if she were her child.

But it touched a social nerve that seems increasingly sensitive to the intrusiveness of mobile phone technology.

"This fuss happened at a time when there is an uprising in Egypt, violence in Syria – why?" asks Will Norman, an anthropologist and the author of "Charm Offensive," a survey into British civility. "Because people mind about these things," he says. “There has been growing use of this stuff. The technology has become so omnipresent that people are beginning to question it, to realize, this behavior seems rude."

New Rules?

Debretts, publisher of etiquette handbooks as well as its better known encyclopedia of British aristocrats, has responded to this feeling with a new guide to the correct use of communications technology. Most Brits will likely find it too strict, with its chastisement of anyone who speaks on the phone in front of their friends – “the height of bad manners."

Angela Marshall, an image consultant who writes a blog on etiquette, says mobile phone manners vary from place to place and between ages, with young people in London the rudest.

“But companies, businesses, will start to pick up on the fact that manners do matter and start to develop rules about the use of mobiles," she says.

In society at large, meanwhile, Mr. Norman has begun to observe what he calls “nudges” which suggest new, unofficial tenets are evolving on when and where the use of mobiles are unacceptable.

He cites the increasing number of shops and businesses that have started putting signs up banning the use of mobile phones during transactions.

The experience of Darren Room, proprietor of Little Red Roaster, a coffee shop in Norwich, east England, suggests that people can respond quickly and uncomplainingly to new rules.

Last year, he put up a sign in his café requesting customers desist from talking on the phone while they were being served.

“When we put the sign up we weren’t even thinking of etiquette but rather the fact that when someone was speaking on the phone we couldn’t communicate with them properly to give them top quality service," he says.

He has since taken the sign down. “It’s not really necessary any more because people understand it’s not the done thing."

“The odd person does stand there talking on the phone,” he adds, “but I and my staff now feel much more confident about not serving them until their conversation is finished."